Hydraulic truck body tilting mechanism



March 10, 1953 N. D. PEARSON HYDRAULIC TRUCK BODY TILTING MECHANISM 2 SHEETS-SHEET 1 Filed July 18. 1951 A \aw & l N VEN TOR.

1? m f P M a W 4 0 z ATTORNEYS 2 SHEETSSHEET 2 W /----L -:-x

N. D. PEARSON HYDRAULIC TRUCK BODY TILTING MECHANISM March 10, 1953 Filed July 18, 1951 y l N VE N TOR. %i"i7Zd7ZaP8ai1S are,

W Am Patented Mar. 10, 1953 -I-IDRAULIC TRUCK BODY TILTING -MECHANISM Norman 1).-Pearsonfvt hittier, Iowa Application July =18, 1951, l'S'erialw- No. 237,32 1

2"Claims. 1

Ilhis-invention relates-to motor trucksparticularly-ofthe-typehaving elongated platforms or beds-and such as used for hauling-heavyv machinery and equipment, and in particular this invention relates to a truck having a pivotally wmounted or tilting body-or bed and wherein the mounting and :tiltinginstrumentalities are positioned whereby the trailingend-of the bed moves downwardly to the ground or tea surface upon which 7 the truck is 1 positioned "The purpose of this --i nvention (is to arrange tilting elements of -a truck bed or body wherein the elements are positionedto drop the trailing --end of the -.bed downwardly for loading and wherein thesame ele'ments bring the :be'd back to a horizontal position and lock the bed in the horizontal position.

Various devices have (beenrprovided for tilting bodiesandbeds-of motor trucks, particula'rly'for dumping products from the trucks, however, where trucks :are usedfor hauling tractors and -heavy-farmequipment it is difficult to drop the rearendof the bed sufficientlyto permit driving ayehicle thereon. With this thought in mind this invention contemplates an elongated T truck body 5 having -a bed pivotally mounted slightly -ahead-oi the rear axle of the truck whereby with 'hydraulic cylinders pivotally connected to the chassis at a :similar =point-and also connecte'd' to togglelactingl levers beneath the bedof the truck maybe dropped-downwardly to a .comparatively --sma 11 angle with the surface eupon which the truck nis positioned.

The object of this-invention is, therefore, to

provide means for mountingtiltingand levating elements on a pivota-lly mounted bed of a truck body whereby the bed is readily tilted to an inclined position and :also whereby the bed is returned to a horizontal position.

Another object of "the invntion is to provide tilting instrumentalities for truck bodies with which a tilting 'bedmay bemounted'on the chassis -of a truck now in use.

A further object of the invention is-toiprovide a tru'cbhaving a tiltingbedwhich is 0f:a:*simple and economical construction.

With these and other":obj'eets 'and advantages inview-the invention embodies a motor "truck having a chassis mounted on wheels with a bed pivotally mounted on the chassis, with toggle acting levers pivotally mounted on the chassis and connected to the tilting bed and with hydraulic cylinders pivotally mounted on the chassis and connected to the toggle levers whereby the levers are actuated by the cylinders to tilt the i rangement 6f the operatin instrumentalities.

bed and also to return thebed to a horizontal position.

=Other features and advantages of the invention -=wil1 appear Qfrom the following description taken connection with the drawings wherein:

LEigure lis a side elevati'onal vi'ewshowingm truck having -a tilting "bed with the' bed indicated in the tilted position in dottedlines.

I Figure 2lis a plan tiewo'fthe .t'ruekwith parts broken away showing "the construction land "arore"? showin *the pivotal "mounting Lo f the bed on the chassis "df the truck.

Figure 7 is a cross section through thepivotal mounting of the 'b'edbntlie truck taken o'n'line 'ii of Figure 6. V

Figure 8 is a detail showing one of theh'angers V forsusmndingthe bearings "for'p'ivotallymounting the "toggl'eilevers "on'the "chassisof the l truck.

Figures LiS a planwiewisnowing"the-arrange- 'mentrof'zthe togglelevers onthe shaftiiournaled in "the bearings 'suspendedfroin' the :chas'si's, illustratedin'FigureiS.

"Figure l-'0 is :a diagrammatic Wie'W 'iilll'ls'tratifig aimethodofsupplyinglfiuid under. pressure toi'the hydraulic cylinders.

Referring 'now to the di'awings wherein "like reference characters denote oorrespondingmar ts the improved truck be'd tilting mechanism of this invention "includes a truck lbedi-having a platform or "floor m mounte'dbyiljoists H .on longitudinally dispose'dbeams Y [2 and "l 3,-a shaft "it by which -the bed is pivotally -mounted ion spaced just ahead of and above the rear axle to facilitate downward movement of the cylinders in the tilting operation and the piston rods 23 and 24 which extend from the cylinders are pivotally connected to arms 25 and 26, respectively on the rocker shaft ll.

The rocker shaft ll is also provided with arms 21 and 28 which, with the arms 25 and 26, are rigidly secured to the shaft, preferably by welding and the extended ends of the arms 21 and 28 are pivotally connected to links pivotally mounted on the beams l2 and I3 of the tiltin bed.

As shown in Figure 4, the arm 21 is pivotally connected to links 29 and 30 by a pin 3| and the upper ends of the links are pivotally mounted on the beam 12 by a pin 32. The arm 28 is pivotally connected to links 33 and 34 by a pin 35 and the links are pivotally connected to the beam 13 by a pin 30.

With the parts arranged in this manner fluid under pressure applied to the forward ends of the cylinders 18 and i9 drives the connecting rods outwardly from the position shown in Figure 1 whereby the toggle levers are actuated from the position shown in Figure 1 to that shown in Figure 3 and in this movement the bed i8 is tilted; and when fiuid under pressure is applied to the outer ends of the cylinders the piston rods are drawn inwardly with the arms 23 and 24 drawing the arms 25 and 26 upwardly until the pins 31 and 35 pass over the dead center, to the position shown in Figure 1 whereby the bed is locked in a horizontal position.

The shaft M by which the bed is pivotally mounted on the chassis is mounted by split bearings 37 and 38 on the side beams of the chassis, as illustrated in Figures 6 and '7, with the ends of the shaft extended through and Welded to the beams 12 and I3 and extended into the short beams 39 and 40. The ends of the shaft may be provided with set collars 4|, and with bearings 31 and 38 split the shaft is removable from the bearings.

' The shaft I! is journaled in bearings 42 which are suspended from the chassis l by hangers 43, as shown in Figure 8.

It will be understood that fluid under pressure may be supplied to the hydraulic cylinders l8 and 19 by suitable means and in the design shown connections 44 and 45 are connected by tubes 48 and 41 to a spool valve 48, one side of which is connected by a tube 49 to a tank or reservoir 50, and the other by a connection 5! to the discharge side of a pump 52. The suction of the pump is connected to the tank 50 by a connection 53.

The valve 48 is operated by a hand lever 54 whereby the fluid under pressure may be applied to either of the ends of the cylinders, as may be desired. It will also be understood that a valve of any other suitable type may be used and the valve may be operated by other suitable means.

It will be understood that modifications may be made in the design and arrangement of the parts without departing from the spirit of the invention.

What is claimed is:

1. A motor truck having a chassis mounted on front and rear wheels, a rear axle through which the chassis is mounted on the rear wheels, a tilting bed positioned on the chassis mounted for pivotal movement about a horizontal axis, means pivotally mounting the said bed on the chassis at a point spaced slightly ahead of the said rear axle, a plurality of hydraulic cylinders having piston rods extended therefrom pivotally mounted on the chassis at a point also spaced slightly ahead of the said rear axle, a rocker shaft suspended from the chassis and positioned at a point at the rear of the said rear axle, pairs of arms carried by said rocker shaft, links pivotally connected at one of the ends thereof to the said tilting bed and positioned with the other of the ends thereof pivotally connected to one of the pairs of arms of the rocker shaft, and means for pivotally connecting the other of said pair of arms of the rocker shaft to the piston rods extended from the hydraulic cylinders, said links and arms positioned whereby with the bed positioned horizontally upon the chassis the connections between the links and arms pass beyond the dead center thereby securing the bed in the horizontal position.

2. A motor truck having a chassis mounted on front and rear wheels, a rear axle through which the chassis is mounted on the rear wheels, a tilting bed positioned on the chassis and mounted for pivotal movement about a horizontal axis, means pivotally mounting the said bed on the chassis at a point spaced slightly ahead of the said rear axle, hydraulic cylinders having piston rods extended therefrom pivotally mounted on the chassis at a point also spaced slightly ahead of the said rear axle, a rocker shaft suspended from the chassis and positioned at a point at the rear of the said rear axle, pairs of arms carried by said rocker shaft, links pivotally connected at one of the ends thereof to the said tilting bed and positioned with the other of the ends thereof pivotally connected to one of the pairs of arms of the rocker shaft, means pivotally connecting the other of the said pair of arms of the rocker shaft to the piston rods extended from the hydraulic cylinders, said links and arms positioned whereby with the bed positioned horizontally upon the chassis the connections between the links and arms pass beyond the dead center thereby securing the bed in the horizontal position, means for supplying fluid to one of the ends of the hydraulic cylinders for tilting the bed, and means supplying fluid to the opposite ends of the cylinders for drawing the bed back to a horizontal position.

NORMAN D. PEARSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,705,892 Ballert Mar. 19, 1929 2,146,166 Anthony et al. Feb. 7, 1939 2,220,815 Feilcke Nov. 5, 1940 2,456,805 Wohlforth Dec. 21, 1948 2,470,360 Messick May 17, 1949 

